Toggle Realtime GI at runtime?

I'd like to provide users an option to disable Realtime GI at runtime, for performance reasons, if they choose to. I don't see a direct way to do this. I considered simply setting the DynamicGI.updateThreshold to a very high value, but I assume that just prevents some aspects of Realtime GI from running, and that the system is still doing a bunch of work to decide if the threshold has been reached.

Is there any runtime option to toggle Realtime GI, to avoid the performance hit?